有機合成化学協会誌
Online ISSN : 1883-6526
Print ISSN : 0037-9980
ISSN-L : 0037-9980
70 巻 , 3 号
選択された号の論文の9件中1~9を表示しています
巻頭言
総説および総合論文
  • 木村 正成
    2012 年 70 巻 3 号 p. 216-226
    発行日: 2012/03/01
    公開日: 2012/03/23
    ジャーナル 認証あり
    Ni catalyzes homoallylation of aldehydes with 1,3-dienes in the presence of triethylborane to provide bishomoallyl alcohols. Triethylborane serves as reducing agent and Lewis acid to promote the homoallylation via oxanickelacycles. Under similar conditions, Rh catalyzes the reductive coupling reaction of aldehydes and 1,3-dienes to provide homoallyl alcohols while Pd catalyst promotes the ene-type reaction to provide dienyl homoallyl alcohols.
    Triethylborane also activates allylic alcohols to form π-allylpalladium key intermediates by oxidative addition of Pd(0) toward allylic C-O bonds and achieves amphiphilic allylations. A combination of Pd catalyst and triethylborane effectively promotes 3-hydroxy-4-pentenoic acid to undergo β-decarboxylative C-C bond cleavage reaction via β-vinyloxapalladacyclopentanone to provide conjugated diene and carbon dioxide.
  • 岡村 浩昭, 岩川 哲夫, 濱田 季之
    2012 年 70 巻 3 号 p. 227-239
    発行日: 2012/03/01
    公開日: 2012/03/23
    ジャーナル 認証あり
    The base-catalyzed Diels-Alder (DA) reaction is a unique cycloaddition, which comprises the combination of electron deficient dienophiles and dienes having acidic functional groups that are activated by bases. It is quite opposite to the well-known Lewis acid-catalyzed DA reactions that include electron rich dienes and dienophiles that are activated by Lewis acids or Brønsted acids. In our continuous effort to develop the base-catalyzed DA, we have found that three different classes of compounds, 3-hydroxy-2-pyrone, 3-hydroxy-2-pyridone, and α-tropolone can be used as dienes suitable for the DA reaction. All the base-catalyzed DA reactions we have developed are accelerated by mild amine bases and give the corresponding products in quantitative to moderate yields. As well as acid-catalyzed DA reactions, chiral base catalysts and/or chiral dienophiles provide the enantioselective DA reactions. Because the resulting DA adducts that have various functional groups and rigid bicyclic ring systems, are attractive building blocks for natural products, particularly for cyclohexene oxides and carbasugars, some synthetic applications to give biologically active compounds using the DA adducts are described.
  • 安井 英子, 加藤 國基
    2012 年 70 巻 3 号 p. 240-249
    発行日: 2012/03/01
    公開日: 2012/03/23
    ジャーナル 認証あり
    Emergence of resistance to anticancer agents is a serious problem in cancer chemotherapy. We studied on the suppression of anticancer drug resistance targetting the overexpressed glutathione (GSH) in apoptosis-resistant tumor cells and glyoxalase I (GloI). GloI is an enzyme that plays a role in the detoxification of methylglyoxal utilizing GSH as an essential cofactor. Inhibitors of GloI have been found to exhibit antiproliferative effects on cancerous cells. Hence, potent GloI inhibitors could proved to be valuable anticancer agents. COTC, an inhibitor of GloI isolated from the culture broth of Streptomyces griseosporeus, had no effect on GloI in the absence of GSH. We reexamined the reaction of COTC with GSH and found that STCG was the real inhibitor of GloI. AsPC-1 cells show the drug-resistance against anticancer drugs because of the over-expression of GSH. When AsPC-1 cells were treated with several anticancer drugs in the presence of COTC, the sensitivity of AsPC-1 cells to CDDP and melphalan was significantly increased. Next, we synthesized ACDC containing adriamycin as an anticancer drug in a molecule. Treatment of ACDC with GSH released adriamycin and SDCG. Evaluation of ACDC against adriamycin-resistant L1210 cells showed significant increase of sensitivity and the prolonged life span of mice bearing P388 leukemia was observed.
  • 長島 生, 清水 弘樹
    2012 年 70 巻 3 号 p. 250-264
    発行日: 2012/03/01
    公開日: 2012/03/23
    ジャーナル 認証あり
    The use of microwaves for the effective heating of foods is a familiar aspect of our daily lives. Beginning in 1986 and especially in the last decade, microwave irradiation has also become increasingly popular as a tool for chemical synthesis. It has mainly been used as an effective heating tool and, as a result, has allowed higher yield and/or shorter reaction times. More recently it has since suggested that microwave irradiation is not only an effective heating tool but also allows for control over other factors in chemical synthesis. Based on this premises, we have demonstrated the effective use of microwave for peptide, carbohydrate and drug library syntheses and for the development of a new process synthetic concept for Rosiglitazone preparation.
  • 小澤 智宏, 高畑 祥, 北川 英男
    2012 年 70 巻 3 号 p. 265-275
    発行日: 2012/03/01
    公開日: 2012/03/23
    ジャーナル 認証あり
    Bacterial enoyl-acyl carrier protein (ACP) reductases (FabI and FabK) catalyze the final step in each cycle of fatty acid biosynthesis and are attractive targets for the development of new antibacterial agents. Here, we report the development of novel phenylimidazole derivatives as potent FabK inhibitors with antibacterial activity against Streptococcus pneumoniae. A representative compound, 1-{[4-(4-bromophenyl)-1H-imidazol-2-yl]methyl}-3-[5-(pyridin-2-ylthio)thiazol-2-yl]urea (53) showed strong FabK-inhibitory activity (S. pneumoniae FabK IC50 0.0024µM) and potent in vitro antibacterial activity against S. pneumoniae (MIC 0.25 µg/mL). MIC50 and MIC90 of compound 53 against 29 clinical isolates of S. pneumoniae, including penicillin-resistant strains, were 1 and 4µg/mL, respectively. Since an elevated MIC value was observed with a S. pneumoniae mutant possessing an amino acid substitution in FabK, the antibacterial activity of the compound was considered to be due to the inhibition of FabK. Moreover, this compound showed no significant cytotoxicity. These results suggest that compound 53 is a candidate for anti-pneumococcal agent.
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